The present invention relates generally to inkjet printheads, and more particularly to a wide-array inkjet printhead assembly.
A conventional inkjet printing system includes a printhead and an ink supply which supplies liquid ink to the printhead. The printhead ejects ink drops through a plurality of orifices or nozzles and toward a print medium, such as a sheet of paper, so as to print onto the print medium. Typically, the orifices are arranged in one or more arrays such that properly sequenced ejection of ink from the orifices causes characters or other images to be printed upon the print medium as the printhead and the print medium are moved relative to each other. Typically, a mounting assembly and a media transport assembly establish relative positioning and movement of the printhead and the print medium, respectively.
In one arrangement, commonly referred to as a wide-array inkjet printing system, a plurality of individual printheads, also referred to as printhead dies, are mounted on a single carrier so as to create a wide-array inkjet printhead assembly. As such, a number of nozzles and, therefore, an overall number of ink drops which can be ejected per second is increased. Since the overall number of drops which can be ejected per second is increased, printing speed can be increased with the wide-array inkjet printing system.
Positioning of the wide-array inkjet printhead assembly, however, requires proper alignment between the carrier of the printhead dies and the mounting assembly. Misalignment between the carrier and the mounting assembly can adversely affect performance of the inkjet printing system. Misalignment between the carrier and the mounting assembly, for example, can result in ink drop trajectory errors, printing swath gaps, and/or pen-to-paper spacing problems which degrade print quality. Thus, in order to avoid misalignment between the carrier and the mounting assembly, relative positioning between the inkjet printhead assembly and mounting assembly should be controlled.
Accordingly, a need exists for controlling relative positioning of a wide-array inkjet printhead assembly which includes a plurality of printhead dies mounted on a single carrier.
One aspect of the present invention provides an inkjet printing system. The inkjet printing system includes a mounting assembly including a plurality of datums and an inkjet printhead assembly mounted in the mounting assembly. The inkjet printhead assembly includes a carrier contacting at least one of the plurality of datums and a plurality of printhead dies each mounted on the carrier.
In one embodiment, the plurality of datums includes a first datum and a second datum spaced from the first datum. As such, the carrier of the inkjet printhead assembly is mounted between and contacts the first datum and the second datum.
In one embodiment, the plurality of datums includes a first pair of datums and a second pair of datums spaced from the first pair of datums. As such, the carrier of the inkjet printhead assembly is mounted between and contacts the first pair of datums and the second pair of datums. In one embodiment, the second pair of datums is offset from the first pair of datums.
In one embodiment, the mounting assembly includes a first carriage rail and a second carriage rail opposed to and spaced from the first carriage rail, wherein the first carriage rail and the second carriage rail each include at least one datum of the plurality of datums. As such, the carrier of the inkjet printhead assembly is mounted between the first carriage rail and the second carriage rail and contacts the at least one datum of each of the first carriage rail and the second carriage rail.
In one embodiment, the carrier has a first side and a second side parallel with the first side. As such, the first side of the carrier contacts the at least one datum of the first carriage rail and the second side of the carrier contacts the at least one datum of the second carriage rail. In one embodiment, the carrier has a third side and a fourth side both oriented at an angle to the first side and the second side of the carrier. As such, the third side of the carrier contacts the at least one datum of the first carriage rail and the fourth side of the carrier contacts the at least one datum of the second carriage rail.
In one embodiment, the carrier includes a first notch formed in the first side thereof and a second notch formed in the second side thereof. As such, the first notch receives the at least one datum of the first carriage rail and the second notch receives the at least one datum of the second carriage rail. In one embodiment, the carrier includes a first flange projecting from the first side thereof and a second flange projecting from the second side thereof. As such, the first flange contacts the at least one datum of the first carriage rail and the second flange contacts the at least one datum of the second carriage rail.
In one embodiment, the at least one datum of the first carriage rail includes a portion projecting from the first carriage rail toward the second carriage rail and the at least one datum of the second carriage rail includes a portion projecting from the second carriage rail toward the first carriage rail.
In one embodiment, the inkjet printhead assembly also includes a second carrier and a second plurality of printhead dies each mounted on the second carrier. As such, at least one of the plurality of datums or a pair of the plurality of datums is interposed between and contacts the first named carrier and the second carrier.
Another aspect of the present invention provides a method of forming an inkjet printing system. The method includes providing a mounting assembly including a plurality of datums, providing an inkjet printhead assembly including a carrier and a plurality of printhead dies each mounted on the carrier, and mounting the carrier in the mounting assembly and contacting at least one of the plurality of datums.
Another aspect of the present invention provides a mounting assembly. The mounting assembly includes a carriage adapted to receive a carrier having a plurality of inkjet printhead dies mounted thereon and a plurality of datums formed on the carriage. As such, the plurality of datums are adapted to position the carrier relative to the carriage.
Another aspect of the present invention provides a method of forming a mounting assembly. The method includes providing a carriage adapted to receive a carrier having a plurality of inkjet printhead dies mounted thereon and forming a plurality of datums on the carriage. As such, the plurality of datums are adapted to position the carrier relative to the carriage.
Another aspect of the present invention provides an inkjet printhead assembly adapted to be mounted in a mounting assembly including a plurality of datums. The inkjet printhead assembly includes a carrier and a plurality of printhead dies each mounted on the carrier. The carrier is adapted to contact at least one of the plurality of datums of the mounting assembly and position the inkjet printhead assembly in three dimensions relative to the mounting assembly.
In one embodiment, the present invention provides a wide-array inkjet printing system which includes a plurality of datums which establish relative positioning of a carrier having a plurality of printhead dies mounted thereon.